United States Adopted Name

[2] The USAN Council began in June 1961 after the AMA and the USP jointly formed the AMA-USP Nomenclature Committee.

[7][8] USANs assigned today reflect both present nomenclature practices and older methods used to name drug entities.

As newer drugs became chemically more complex and numerous, nonproprietary names based on chemistry became long and difficult to spell, pronounce, or remember.

Current nomenclature practices involve the adoption of standardized syllables called "stems" that relate new chemical entities to existing drug families.

The recommended list of USAN stems is updated regularly to keep pace to accommodate drugs with new chemical and pharmacologic properties.

Therefore, it is highly desirable to the pharmaceutical company, the various nomenclature committees, and the medical community in general that a global name be established for each new single-entity compound introduced.